Malaria Test Improves Diagnosis for Imported Cases

A highly sensitive blood test that quickly detects even the lowest levels of malaria parasites in the body could make a dramatic difference in efforts to tackle the disease.

The diagnosis of malaria relies on parasite detection by microscopy or antigen detection, but both methods sometimes fail to detect low-density infections and a technically less challenging test has now been evaluated.

Scientists, led by those at the Hospital for Tropical Diseases (London, UK) determined the diagnostic accuracy, in febrile returned travelers, of a new malaria loop-mediated isothermal amplification (LAMP) kit. The LAMP technique was compared with existing methods. Between January 24, 2011, and July 20, 2011, 705 blood samples of suspected imported malaria cases in the UK, were tested with microscopy, nested polymerase chain reaction (PCR) and the malaria LAMP test.

DNA was purified from whole blood using “PURE” extraction technology comprising customized plastic ware, hardware, and reagents supplied by Eiken Chemical Co., Ltd. (Tokyo, Japan; www.eiken.co.jp). This company also supplied the real time LA‐320 C turbidimeter, and the LF‐160 Simplified LAMP Reactor for assaying the reactions. There was 100% concordance between LAMP and nested PCR for the 56 microscopy positive samples. However, there were 14 LAMP‐positive samples that were negative by both microscopy and nested PCR.


LAMP was faster than PCR tests, which require specialized laboratory equipment, costly reagents and advanced training. It was also more accurate than microscopic examination of blood slides, which require a trained specialist to identify the malaria parasites. LAMP detected cases of low-level malaria parasite infection that were missed by expert microscopy, and achieved accuracy similar to that of PCR down to very low levels.

Colin J. Sutherland, PhD, MPH, a clinical scientist and the senior author, said, “An important advantage of LAMP is that nonspecialist staff in any hospital in the UK will be able to accurately and rapidly detect the presence of malaria parasites, and immediately begin treatment without waiting for confirmation from local experts or specialist laboratories. This speed of diagnosis can make the difference between an uncomplicated episode of malaria that rapidly responds to treatment, and progression to severe disease, organ failure, and heightened risk of death.” The study was published on April 30, 2013, in the Journal of Infectious Diseases.

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Hospital for Tropical Diseases
Eiken Chemical Co., Ltd